1. Technical Field
The present disclosure relates to a magnetic disk device that includes a floating magnetic head including a heating element for making a head element part protrude toward a magnetic disk by thermal expansion and controls a floating distance of the head by increasing or decreasing current supplied to the heating element.
2. Related Art
In a magnetic disk device including a floating magnetic head assembly, a magnetic disk and a magnetic head assembly are assembled in a case, and a head floating distance has been further decreased as the recording density has been increased in recent years. However, a head floating distance varies depending on the change in atmospheric pressure. If a head floating distance is excessively decreased, there is a concern that the magnetic head and the magnetic disk come into contact with each other. In contrast, if a head floating distance is excessively increased, there is a concern that the performance of the head deteriorates and writing/reproducing errors occur. A method, which adjusts a head floating distance in accordance with the change in atmospheric pressure, has been proposed in recent years in order to avoid these problems. For example, a magnetic disk device, which includes an atmospheric pressure sensor which detects the atmospheric pressure and stabilizes a head floating distance by changing the load of a magnetic head in accordance with the change in atmospheric pressure, has been disclosed in Japanese Unexamined Patent Application Publication Nos. 63-273287 and 09-063220.
In the magnetic disk device including the atmospheric pressure sensor, there has been a demand for improved accuracy of the control of the head floating distance that is achieved by making the atmospheric pressure sensor be received in a case. However, the demand has not been achieved at present due to the problem of cleanliness. The specific position of the atmospheric pressure sensor has not been described in Japanese Unexamined Patent Application Publication No. 63-273287. In Japanese Unexamined Patent Application Publication No. 09-063220, an atmospheric pressure sensor is mounted on the outer wall of a head disk assembly.